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410 Uppsatser om Timber damages - Sida 19 av 28
Produktivitet och lönsamhet vid skogsbränsleuttag i klena gallringar : en tidsstudie av Vimek 608 BioCombi i contortabestånd
The annual demands for forest fuels increases in Sweden. At present, large unutilized biomass resources is found in young, dense forests from which about five million oven-dry tonnes (ODt) (23 TWh) could annually be extracted as forest fuel. But harvesting small trees give high logging costs and new cost-efficient harvesting techniques are therefore required. The aim was to study the productivity of Vimek 608 BioCombi in forest fuel thinning of Lodgepole pine and to calculate the economy of the harvesting and estimate the thinning quality. The time study was performed in Åmarken in the county of Västerbotten.
Ny kölkonstruktion på segelbåtar
This Master Thesis is a product development project that has been carried out in cooperation withSvea Teknik AB. The company has developed an apparatus for attachment of a keel to a hull base ofa boat. The purpose for this thesis has been to compare a new concept of keel attachment incomposite material to thetraditionaldesign solution. This new keel attachment minimizes thedamages that may arise on the keel and the hull of the boat in shape of stresses impacts at grounding.Today it is a problem, relating to keel attachment on sailing boats having a fin keel or a bulbous keel.The manufacture focus on developing larger draught and shorter keel blades. The overall purpose isto increase performance of the sailing boat.The task for this thesis was to develop a concept of keel blade in composite material and investigateattachment to a sheet-shaped element.
Kartläggning av spånprodukter vid Sävar såg
A change towards using more biofuels than fossil fuels is taking place in Sweden, and in many other parts of the world. This makes the use of fuel pellets increasingly popular, causing a greater demand for sawmill sawdust products. There is a trend towards the use of multiple types of shredders, instead of a single type in each sawmill. The purpose of the study was to characterize the different flows of saw particles that can be found at Sävar såg when cutting thick or thin wood with different cutting techniques. The saw particles size, shape, moisture content and heat value were analysed by the cutting stations: first cutting fast and slow, second cutting fast and slow, grading fast and slow and planning.
Tillvaratagande av GROT i skärgårdsnära miljö :
The main aim of this study was to investigate and compare different methods for the extraction of forest fuel from environments close to an archipelago. The study was based on relevant literature and published reports as well as personal communications.
Forestry has traditionally been characterized by intense efforts to rationalize and mechanize the cutting technique used for timber and pulpwood. In line with the increasing importance of forestry, more concentrated efforts can be expected in the area of techniques and methods, especially for the above-mentioned product lines.
In Sweden, forestry is of major importance and the Swedish economy and standard of living have mainly been created based on the revenues generated from it. Thus, it is vital that Swedish forests are harvested in an efficient and responsible manner.
The demand for biofuel is growing and today accounts for 15% of total Swedish energy production, a share that will probably increase.
This study is based on three research questions, which are described under the heading of Aim. The results reveal that the most profitable method for handling forest fuel is the traditional one, which is also the most commonly used method in southern Sweden, namely the stockpiling of logs in a clearing by means of forwarders followed by splintering at the place from where they will be distributed.
Today, the high cost of barge transport required for the extraction of forest fuel in an archipelago environment renders such operations unprofitable.
Timmerlängder till Iggesunds sågverk
Det råder hård konkurrens på marknaden för sågade trävaror. Längdkrav på furuprodukter var tidigare sällsynt men blir allt vanligare. Idag efterfrågas längre och längre längder, helst ska sågade trävaror vara över 42 dm (vilket motsvaras av timmerlängder över 43 dm). Iggesunds sågverk ställer sig frågan om det finns möjligheter till en bättre längdanpassning av sågverkets timmerlängder till marknadens krav, och om en sådan förändring skulle löna sig?
Detta arbete tittar på tre scenarier till förändrade timmerlängder och hur de påverkar Iggesunds sågverks lönsamhet.
Avancerad hjärt-lungräddning med mekaniska eller manuella kompressioner : Uppfattningar hos ambulanspersonal om kompetens, övning, patientrisk och överlevnad
Study objectives:Examine ambulance personnel?s perceptions of skills / training and knowledge with regards to the existing mechanical / manual compressions and frequency of training during a work shift. Do ambulance personnel think that mechanical compressions increase survival? Are there concerns that the device could damage the patient?Design: A cross-sectional study, quantitative approach with qualitative elements was conducted.Methods:Questionnaire form, which was answered by 44 ambulance personnel in an ambulance organisation in Sweden. Participants were on a scale of 1-5 to select how they agree with the claims of the study form and also submit their own comments.
Uppdatering av båtnadskalkyl med hänsyn till nya faktorer :
Sweden have 419 000 km road in the country and about half of these roads is forestroads. The forest road net most important mission is to make it possible to deliver wood from the forest to the industries. With a raw material that is spread over a large area the road network is important. Each year has the forest road network been extended with about 1 700 km new roads. To decide if a new road is to be built different forest road cost estimation models has been used.
Vattensork och åkersork - skadegörare i svensk fruktodling
There are two species of voles that cause damage in Swedish fruit production: the water vole (Arvicola terrestris) and the field vole (Microtus agrestis). Both species make the most damage during the winter season. The water vole makes subterranean burrows and cause serious damage by gnawing on the tree roots. The field vole seldom makes burrows and gnaws the bark at the base of the tree trunk. In recent years there have been several reports about increasing vole damage.
ideellt skadestånd till närstående vid psykiska besvär
Ofta rapporterar massmedia om brott som t.ex. mord, våldtäkt och misshandel. Den ena gärningen är brutalare än den andra. Denna uppsats behandlar ideellt skadestånd för sveda och värk som under vissa omständigheter kan tilldömas den som åsamkas psykiska besvär, till följd av underrättelsen om att en nära anhörig uppsåtligen har berövats livet. Effekterna av det psykiska lidande som närstående till ett brottsoffer tvingas utstå vid grova brott är ofta påtagliga för den som drabbas, varför skadestånd ev.
Utvärdering av ett silotorksystem för spannmål utrustat med omrörare :
The aim of this study was to evaluate the stir drying method, for drying of grain during Swedish conditions. The evaluation was done during the harvest year 2004, on four farms with stir driers. The driers were evaluated for their energy consumption, design, stirring effectiveness and how much time the farmer has to spend on every tonne of grain. A comparison was also done with conventional Swedish high temperature driers. Totaly six batches of grain from stir driers were examined, mostly winter wheat, but also barley and wheat.
Matarhjulens dubbinträning i timmer : Undersökning av dubbskador som matarhjulens mönster orsakar på timmer, deras uppkomst och hur man kan motverka dem med olika dubbmönster
Detta examensarbete har gjorts på uppdrag av Rottne Industri AB och berör matarhjulens dubbinträngning i virket. Matarhjulen sitter monterade i skördaraggregatet i skördaren, en skogsmaskin som används vid skogsavverkning. Då inträngningen, som uppstår av dubbarna på matarhjulen, är för stor (>5mm) bildas skador på virket vilket är ett utbrett problem inom skogsmaskinindustrin. Studien kartlägger de vanligaste dubbmönstrens skadeåverkan under kontrollerade och vetenskapliga förhållanden där testerna är designade för att efterlikna verklig skogsavverkning.I studien utförs två tester. Det första visar sambandet mellan presskraft och inskjutningsmått för respektive dubbmönster.
Identifiering av gallringsbehov med hjälp av flygburen laserskanning :
Thinning is one of the most important silvicultural activities in middle aged forests, partly to minimize damages and partly because it leads to earlier harvesting revenues and increases the value of the remaining trees. There are many different indices used to describe stand density and thereby the need of thinning in forests today. Studies have shown that forest variables can be estimated with high accuracy using airborne laser scanning and it is likely that the method could also be used to estimate forest density indices. In this study, the possibility of using the forest density index ?H² to determine and map priorities for thinning operations for a forest area was examined.
Flygburen laserskanning kopplat till skördarmätning för datainsamling till operativ planering :
The requirements for operative planning activities are increasing. The forest industry wants to gain better control over wood flow. A felling that is more market adjusted is desirable. However, this causes problems in the operative planning process because of the data collection methods used today. Data about timber assortments and data about the distribution of the tree diameter, etc., are often lacking.
Airborne laser scanning is used to a greater extent than before for estimation of forest variables and should perhaps be used to the same extent in operative planning activities as well.
Simulation of rattan harvests in Indonesia : different harvesting pressures and the resulting patterns
The objectives of this research were to determine whether the natural rattan resources in Sulawesi, Indonesia can cope with the strongly increased harvesting pressure that has occurred over the last centuries. I was furthermore looking for patterns in the rattan population dynamics that might give a hint on how the harvesting system could be improved to ensure a maximum sustainable yield. To
answer these questions, I developed an individual-based model to analyse the dynamics of rattan growth in connection with rattan harvests by locals to identify sustainable levels of rattan harvests around villages in Sulawesi, Indonesia. Scenarios with different harvesting intensities were run to compare the change in harvest amount. For a given harvesting pressure, scenarios with a high number of harvesters and a low harvesting frequency had the same effect as scenarios with high harvesting frequencies and a low number of harvesters.
Skogsåkeriägares inställning till organisationsförändringar :
There are two groups of haulage contractors in roundwood transport , those who are contracted direct by the transport buyer and those who are connected to a freight company which in its turn is contracted by the transport buyer. Today the roundwood haulage is dominated by contractors with one to two lorries. The effort of coordinating transportation for a transport buyer is dependent on how many communication contacts that must be managed (how many individual haulage contractors the transport buyer has to work with). A structural change in the sector that leads to a decrease in the number of haulage contractors but an increase in the capacity of each contractor, makes it possible for a transport buyer to coordinate transports with fewer communication contacts. The reason why a company reaches a certain size can be explained by the number of contracts it makes and manages.